Recoil operated small arm



Feb 9, 1937. A. L. cHr-:vALLll-:R Er AL 2,070,355

HECOIL OPERATED SMALL ARM Filed Dec.

19, 1954 3 Sheets-Sheet 1 Feb- 9, 1937- A. l.. cHEvALLlER ET AL 2,070,355

RECOIL OPERATED SMALL ARM v 5 sheets-sheet 2 Filed Deo. 19, 1934 F eb. 9, 1937.

A. L. CHEVALLIER ET AL RECOIL OPERATED SMALL ARM Filed Dec. 19, 1934 3 Sheets-Sheet 3 A? 9; if@

@MMA digr- Patented F eb. 9, 1937 UNITED STABS RECOIL OPER-ATED SMALL ARM Arnold Louis Chevallier and Thomas Frederick Sanders, Slough, England, assignors to Chevallier Self-Loading Firearms Limited, London,

England `Application December 19, 1934, Serial No. 758,322 In Great Britain January 12, 1934 13 Claims.

The invention relates to an improvement in re arms which is applicable not only to small arms, such as ries and sporting guns, but also to machine guns and light artillery. It is directed to novel means for locking the bolt and for releasing it at the appropriate time so as to allow the residual gases t-o act directly on the bolt and cause it to execute the movements necessary for re-loading. The invention makes use. of an inertia member which moves forward relatively to the gun on the recoil and in its movement actuates a locking member, moving the latter from its normal position where it provides a solid abutment for the bolt, to a position in which it will allow the bolt to travel backwards past it.

It was proposed in U. S. A.. patent specification No. 1,946,388 to use an inertia member in this way which travelled horizontally forwards and then rearwards and upwards to raise a locking member out of the path of the bolt. It has been found, however, in certain cases, that the time occupied by this double journey of the inertia member is too long for satisfactory operation.

According to the present invention the locking arrangement comprises a locking piece actuated by an inertia member; the locking piece has at least one abutment facing rearwards to engage a corresponding abutment on the iixed part of the gun and an abutment facing forwards to engage a corresponding abutment on the bolt and is movable substantially parallel to itself and perpendicular to the longitudinal axis of the gun to release the forward abutment from the abutment on the bolt; the inertia member is mounted to move forwards relatively to the gun on recoil and is so connected to the fixed part of the gun and to the locking piece that in doing so it moves in relation to these two parts in two directions oblique to each other. In the preferred arrangement the inertia member moves obliquely forwards 'and upwards on recoil in relation to the fixed part of the gun and longi tudinally in relation to the locking piece, but the inertia member might just as well move longitudinally forward and be connected to the locking piece in an obliquely slidable manner.

As in the case of the specification above referred to the inertia member is advantageously constructed as a cover over part of the top of the shoe and having depending sides, but in this ,case it is preferably slidable obliquely upwards by means of open ended slots in the depending sides on stud-like projections from the outer sides of the shoe. It would also be possible to use links for guiding the cover if desired. Preferably the abutment faces on the locking piece are substantially perpendicular to the longitudinal axis of the gun. There is then no tendency for the pressure generated by the discharge of the cartridge to cause the unlocking mechanism to operate prematurely, but the bolt is not unlocked until the cover is moved forward by an appropriate amount due to its inertia only.

By means of the invention it is possible to provide a simple direct motion of the locking members Without the intervention of levers or linkwork, thus providing a positive, safe and reliable re-loading mechanism.

The accompanying drawings show an embodiment of the invention as applied to a service rifle, but the modifications necessary for applying the invention to other re arms will be clear to those versed in the art.

In the drawings Figure 1 is an elevation of a part of the riile,

Figure 2 is an elevation corresponding to Figure 1 but partly in section Figure 3 is an elevation and Figurefl a plan of the shoe alone Figure 5 is an elevation and Figure 6 a plan of the bolt Figure 7 is an elevation of the bolt from the right hand side, i. e. opposite to the other elevations,

Figure 8 is an end elevation of the bolt from the rear,

Figure 9 is an inverted plan of the cover,

Figure 10 is an elevation of the same from the right,

Figure 11 is an end elevation of the same from the rear.

Figure 12 is an inverted plan of the locking piece,

Figures 13 and 14 are elevation and end elevation of the same viewed normally, i. e. from left and front respectively.

Figure 15 is an inverted plan of the transverse plate.

Figure 16 is an end elevation of the same,

Figure 17 is a rear end elevation of the latch,

Figure 18 is an inverted plan of the locking disc, and

Figure 19 is a plan of the hammer locking piece cooperating therewith.

In the general assembly of Figures 1 and 2 the shoe I with its associated parts is shown and only so much of the guard 2 as is necessary to understand the invention; the barrel has been removed and is not shown. The guard 2, on which the trigger mechanism is mounted, is attached to the shoe I by a hinge at 3 and a locking device at e.

The shoe I is provided with internal longitudinal grooves 5 as shown in Figures 3 and 4 to accomodate the wings 6 of the bolt l, which may be seen in Figures 5 to 8. By means of these wings the bolt is guided in its travel backl0 wards and forwards during the operation of loading. The movement of the bolt is initiated by the residual gas pressure as in the case of other recoil loading weapons, but the control and locking are effected by a novel combination of parts which will now be described.

An inertia cover 8 shown in Figures 9 to ll is guided by oblique slots 9 in its depending sides on four stud-like projections Iii arranged two on each side of the shoe. A plate I I is screwed on to the cover at each side to protect the sliding surfaces. When the gun is red the recoil tends to leave the cover 8 behind, that isto say to cause it to move forward in relation to the gun itself. The oblique guides cause the cover to rise in executing this forward movement.

The unlocking of the bolt 'l is eifected by means of a locking piece I2 carried inside the cover 8 and shown in Figures 12 to 14. The locking piece n is provided with four lugs I3, two on each side, "o which engage rectangular notches lll in the sides of the shoe I. In normal operation the lugs I3 never leave the notches I4 as will be subsequently explained. The lugs I3 are provided at their n outer ends with projecting lips I5 which slide in "0 undercut grooves I6 in the cover. Similar lips I1 are also provided at the forward end of the locking piece I2 to slide in grooves i8 in the cover. Thus it will be seen that the locking piece participates in the movement of the cover perpendicular to the gun axis, but is free to move longitudinally in relation to it. Accordingly, when the cover moves obliquely forward, the locking piece is raised by the movement of the cover but is constrained to move in a direction purely l perpendicular to the longitudinal axis by the engagement of the lugs I3 in the notches M.

The front face I9 of the locking piece engages the rear face 2f! of a step on the bolt where the rear part 2l of the bolt is` recessed below the 5f)k level of the main part so that when the cover is in its lower or ring position the bolt is locked in place. When on recoil the locking piece I2 has been raised sufficiently for the face i9 to clear the rear face 20 on the bolt 'I, the residual 51.5 gases drive the bolt 'I backwards and the latter then completes the re-loading movements in the usual manner.

The locking piece I2 is held in position in the cover 8 by means of a transverse plate 22 shown 640 in Figures 15 and 16. This plate slides in the grooves I6 of the cover and is inserted during assembly after the locking piece I2. Itis secured in position by a latch 23 shown in Figure l'l which is hinged to the cover at 26 on a screw 65 and is secured at 25 by a screw in a hole with mutilated thread and a lip 26.

The locking piece I2 has a pin 2l' projecting from its rear end into a recess 28 in the transverse plate. A spring 29 (Figure 2) on the pin 7 0 2l urges the locking piece I2 and transverse plate 22 apart, and it will be seen that the tendency of the spring is to return the cover 8 to the lower or normal firing position, since on recoil the transverse plate 22 is carried forward with the 7,5ob mlrvvhilvethe vlocking piece i2 retains its posicorrect position for normal operation of the cover. 1

tion in a longitudinal direction so that the spring 29 is compressed between them.

The forward movement of the cover 8 is limited by the contacting of the front edge of one ci depending sides on a slider 3e (Figure 1) held in o undercut grooves between rails 3l. A lever E2 pivoted to one of the rails 3l normally engages a transverse groove 33 cut right across the rails 3l and the slider 36, holding the slider in the If the lever 32 is turned back the slider Si? be pushed down so as to allow the skirt of the cover 8 to pass; the cover can then ce completely removed from the weapon for inspection or dirs.- mantling. After this the slider :iii itself can also if be removed if desired.

The dimensions of the various parts arc such that with the slider 3d normally positioned the cover 8 in its forward and upward position in contact with the slider the projections te of the shoe I are still in the cover slots and the lugs I3 of the locking piece I2 are still in the notches l 4l, but the front face le of the locking piece l2 is clear of the rear abutment face 2E on the bolt As the cover il returns to its lower position the locking piece l2 comes to rest on the upper edges of the shoe I with the lugs 3 resting on the bottoms of the notches is. This determines the normal firing position of the Y cover 8.

With the arrangement described there might be a risk, on the return of the bolt to the firing position, of the firing pin being carried forward by inertia and prematurely ring the cartridge. u To guard against this an L-shaped lever 34 is 'f' pivoted at a point on its horizontal arm on the rear portion 2l of the bolt 1; the toe 35 of this lever is located in a notch 36 in the bottom face of the bolt and is urged downwards by a spring 3l. The pressure of the spring 3T causes the top 40 end 38 of the lever 34 to project above the level of the rear part 2l of the bolt. When the cover 8 descends and brings the locking piece l2 down, the under face of the locking piece nearly contacts with the top face of the part 2| of the bolt 45 and consequently depresses the top end 38 of the lever 34 against the effect of the spring 3l.

About midway up the vertical arm of the l.- shaped lever 3d there is a step 39 which in the rest position of the lever obstructs the head l0 50 of the firing pin and prevents it from executing its full stroke. Thus when the bolt arrives at the firing position the step 3g prevents the firing pin from moving forward by its inertia after the bolt I is stopped by the arrival of the cartridge in the ring position. Immediately thereafter the cover 8 descends and the locking piece l2 depresses the top end 38 of the lever 36, so that when the hammer 4I comes into action and strikes the head 4Q of the firing pin the step 3960 no longer obstructs the head, and the ring pin can make its full stroke and fire the cartridge.

It is desirable to prevent the gun from being fired unless and until the cover 8 is in the normal firing position. It is not considered .suitable to dimension the lever 34 and the head 49 of the firing pin sufficiently heavily to withstand the action of the hammer and so provide for this safety means. A lever :l2 is therefore fitted to the side of the shoe I and is normally urged upwards by a spring d3 against the depending edge of the cover 8. This lever is always in the upper dotted position of Figure 1 when the cover 8 is away from its normal firing position. The lever is fast with a disc 44 having a notch l5 to coF 75 fio operate with a projection 45 on the tail of the primary sear 41 as shown in Figures 1 and 2. When the lever 42 is depressed by the cover, the projection #i6 is free to move upwards into the notch 45, so `that the scar 4l can release the hammer fil, but when the lever 42 is up the projection 45 makes contact with the periphery of the disc 44 and prevents the rear end of the sear il from rising and thus also prevents the front end from being depressed to release the hammer. A small stud 48 fixed to the shoe cooperates with a peripheral notch 49 on the disc M to limit its movement.

The last mentioned safety device can also be brought into action by hand when desired by the operation of a hand lever 5i] shown in Figure lOon the right hand side of the cover. This n lever is fast with a disc 5| which has a pointed projection 52 on its periphery. In normal operating position the lever 50 is in an oblique direction pointing backwards and upwards and the projection 52 lies flush in a corresponding recess inthe cover 8. When the lever 5U is moved forward to the upright position the projection 52 contacts with a lightly dished metal plate 53 let into the woodwork at the side of the shoe and raises the cover 8. Owing to the position of the projection 52 when the lever 50 is substantially vertical, the downward thrust on the cover due to the spring 29 is incapable of returning it to its firing position. This arrangement is also used if at any time it is desired to loa-d by hand, since means must be provided for holding the cover up to allow the bolt to be withdrawn and then returned to its firing position after the insertion of a fresh cartridge. The hand loading arrangements will not be further described since they do not differ from current practice.

A further safety device is necessary to prevent the accidental discharge of the gun when it is loaded and all the parts are in their normal ring position. This safety device is operated by a lever 54 (Figures l and 10) pivoted in the cover on the left hand side and fast with a disc 55 having a chamfered piece 56 projecting downwards from its periphery as shown in Figure 18. The chamfered piece 56 cooperates with an inverted L-shaped piece 51 shown in detail in Figure 19 and assembled in the gun in Figure l. The piece 5l is attached to the shoe l and the hinge 3 by the bottom of its vertical part. At the angle of the L-piece. 51 a stud 58 projects outwards, and whe-n the lever 54 is moved from a position pointing backwards and upwards to a substantially vertical position, the stud 58 is pressed inwards by the chamfer 56, thus moving the top of the Lpiece 51 inwards against the effect of its vertical part which is made springy. At the end of the horizontal part and facing inwards a projection 59 is provided which is adapted to enter a notch 69 in the hammer breast and thus hold the hammer 4I cocked. Any movement of the trigger will then fail to release the hammer.

What we claim is:-

l. In a recoil loading gun having a breech casing and a breech bolt slidable therein to effect the reloading, a bolt locking arrangement comprising in combination at least one abutment surface on the breech casing substantially perpendicular to the longitudinal axis of the gun and facing forwards, an abutment surface on the bolt facing rearwards and parallel `to the first named abutment surface, a locking piece with abutment `surfaces located to cooperate with both the said abutment surfaces, said locking piece being slidable in a direction parallel to the abutment surfaces and the abutment surfaces between the locking piece and breech casing being of greater extent in the direction of movement of the locking piece than the abutment Surfaces between the locking piece and bolt, an inertia member free to move in a direction having a forward component in relation to the breech casing on recoil, cooperating guiding surfaces on the inertia member and the breech casing to define said direction of movement, and cooperating guiding surfaces on the inertia member and the locking member, the latter guiding surfaces on the inertia ember being inclined in relation to the former guiding surfaces on the same member.

2. In a recoil loading gun having arbreech cas,-V

ing in combination at least one abutment surface on the breech casing substantially perpendicular to the longitudinal axis of the gun and facing forwards, an abutment surface on the bolt facing rearwards and parallel to the first named abutment surface, a locking piece with abutment surfaces located to cooperate with both the said abutment surfaces, said locking piece being slidable in a direction parallel to the abutment surfaces and the abutment surfaces between the locking piece and breech casing being of greater extent in the direction of movement of the locking piece than the abutment surfaces between the locking piece and. bolt, an inertia member free to move in a direction having a forward component relation to the breech casing on recoil, cooperating guiding surfaces on the inertia member and the breech casing inclined to the longitudinal axis of the gun and cooperating guiding surfaces on the inertia member and the locking member parallel to the longitudinal axis of the gun.

3. In a recoil loading gun having a breech casing and a breech bolt slidable therein to eifect the reloading, a bolt locking arrangement comprising in combination at least one abutment surface on the breech casing substantially perpendicular to the longitudinal axis of the gun and facing forwards, an abutment surface on the bolt facing rearwards and parallel to the first named abutment surface, a locking piece with abutment surfaces located to cooperate with both the said abutment surfaces, said locking piece being slidable in a direction parallel to the abutment surfaces and the abutment surfaces between the locking piece and breech casing being of greater extent in the direction of movement of the loci:- ing piece than the abutment surfaces between the locking piece and bolt, an inertia cover over at least a part of the breech casing, depending edges on the cover with oblique guiding slots in a forward and upward direction, projections on the side of the breech easing in engagement with the said guiding slots, and guiding means parallel to the longitudinal axis of the gun between the inertia cover and the locking piece.

4. In a recoil loading gun having a breech casing and a breech bolt slidable therein to effect the reloading, a bolt locking arrangement comprising in combination an inertia cover over at least a part of the breech casing and having grooves on its underside, depending edges on the cover with open ended oblique guiding slots running in a forward and upward direction, projections on the breech casing in engagement with the said guiding slots, a locking piece, lips running longitudinally of the locking piece in engagement with the grooves on the underside of the inertia cover, teeth directed downwards on the locking piece with faces substantially perpendicular to the longitudinal axis of the gun, notches in the sides of the breech casing shaped correspondingly to said teeth and with which the teeth engage, and a step of substantial dimensions on the upper side of the bolt normally in engagement with the front end of the locking piece.

5. In a recoil loading gun having a breech casing and a breech bolt slidable therein to effect the reloading, a bolt locking arrangement comprising in combination an inertia cover over at least a part of the breech casing and having grooves on its underside, depending edges on the cover with open ended oblique guiding slots running in a forward and upward direction, projections on the breech casing in engagement with the said guiding slots, a locking piece, lips running longitudinally of the locking piece in engagement with the grooves on the underside of the inertia cover, teeth directed downwards on the locking piece with faces substantially perpendicular to the longitudinal axis of the gun, notches in the sides of the breech casing shaped correspondingly to said teeth and with which the teeth engage, a step of substantial dimensions on the upper side of the bolt normally in engagement with the front end of the locking piece, and a removable stop on the breech casing in front of one of the depending edges of the inertia cover normally located in contact with the said depending edge when the front face of the locking piece is clear of the step on the bolt but with the other parts still in en- J gagement.

6. In a recoil loading gun having a breech casing and a breech bolt slidable therein to effect the reloading, a bolt locking arrangement comprising in combination at least one abutment surface on the breech casing substantially perpendicular to the longitudinal axis of the gun and facing forwards, an abutment surface on the bolt facing rearwards and parallel to the first named abutment surface, a locking piece with abutment surfaces located to cooper-ate With both the said abutment surfaces, said locking piece being slidable in a direction parallel to the abutment surfaces and the abutment surfaces between the locking piece and breech casing being of greater extent in the direction of movement of the locking piece than the abutment surfaces between the locking piece and bolt, an inertia member free to move in a direction having a forward component in relation to the breech casing on recoil, cooperating guiding surfaces on the inertia member and the breech casing to define said direction of movement, cooperating guiding surfaces on the inertia member and the locking piece, the latter guiding surfaces on the inertia member being inclined in relation to the fo-rmer guiding surfaces on the same member, a forward facing surface fast with the inertia member, and a spring between said surfaces and the rear end of the locking piece.

7. In a recoil loading gun having a breech casing and a breech bolt slidable therein to effect the reloading, a bolt locking arrangement comprising in combination an inertia cover over at least a part of the breech casing and having grooves on its underside, depending edges on the cover with open ended oblique guiding slots running in -a forward and upward direction, projections on the breech casing in engagement with the said guiding slots, a locking piece, lips running longitudinally of the locking piece in engagement with the grooves on the underside of the inertia cover, teeth directed downwards on the locking piece with faces substantially perpendicular to the longitudinal axis of the gun, notches in the sides of the breech casing shaped correspondingly to said teeth and with which the teeth engage, a step of substantial dimensions on the upper side of the bolt normally in engagement with the front end of the locking piece, a detachable plate located in the inertia cover behind the locking piece, and a compression spring between the rear end of the locking piece and the detachable plate.

8. In a recoil loading gun having a breech casing, a breech bolt slidable therein to effect the reloading and a firing pin slidable in the breech bolt, a locking piece slidable in relation to the breech casing in a direction substantially perpendicular to the longitudinal axis of the gun, a step on the bolt normally in engagement with the front end of the locking piece, an L-shaped lever having a horizontal arm and a vertic-al arm and being pivoted at a point in its horizontal arm onV the bolt and provided with a step in its vertical arm, and spring means to urge the outer end of the horizontal arm downwards, the arrangement being that with the outer end of the horizontal arm depressed the step on the lever is in engagement with the head of the firing pin and the top end of the vertical arm is above the level of the part of the bolt behind the step.

9. In a recoil loading gun having a breech casing, -a breech bolt slidable therein to effect the reloading and a iiring hammer, an inertia cover over at least a part of the breech casing, guiding means for the inertia cover directed obliquely forwards and upwards, depending edges to the cover, a lever pivoted to the breech casing and located to Contact with a depending edge of the cover, a spring positioned to urge the lever upwards, and means connected to the said lever for locking the hammer out of action when the lever is raised.

10. In a recoil loading gun having a breech casing, a breech bolt slidable therein to eect the reloading, a firing hammer and a primary Sear cooperating with the hammer, an inertia cover over at least a part of the breech casing, guiding means for the inertia cover directed obliquely forwards and upwards, depending edges to the cover, a lever pivoted to the breech casing and located to contact with a depending edge of the cover, a spring positioned to urge the lever upwards, a disk fast with the lever and provided with a notch in its periphery, a projection on the tail of the primary sear located to enter the notch of the disk when the lever is depressed and to contact with the periphery of the disk when the lever is released by the cover.

1l. In a recoil loading gun having a breech casing and a breech bolt slidable therein to effect the reloading, an inertia cover over at least a part of the breech casing, guiding means for the inertia cover directed obliquely forwards and upwards, depending edges to the cover, a lever pivoted in a depending edge of the cover near the lower margin thereof, a disk fast With the lever, a pointed projection on the disk located to lie flush with the cover edge in one position and to project downwards in the other position, gandk a seating on the breech casing below the 12. In a recoil loading gun having a breech casing, and a breech bolt slidable therein to eifect the reloading, a bolt locking arrangement comprising in combination an inertia cover over a part of the breech casing and having grooves on its underside, depending edges on the cover with open ended oblique guiding slots running Ain a forward and upward direction, projections on the breech casing in engagement with the said guiding slots, a locking piece, lips running longitudinally of the locking piece to engage the grooves on the underside of the inertia cover, teeth directed downward on the locking piece with faces substantially perpendicular to the longitudinal axis of the gun, notches in the sides of the breech casing shaped correspondingly to said teeth and with which the teeth engage, a detachable plate located in the cover behind the locking piece, a compression spring between the rear end of the locking piece and the detachable plate, a step of substantial dimensions on the bolt normally in engagement with the front end of the locking piece, and a removable stop on the breech casing in front of one of the depending edges of the inertia cover normally located in contact with the said depending edge when the front face of the locking piece is clear of the step but with the other parts still in engagement.

13. In a recoil loading gun having a breech casing, a breech bolt slidable therein to eiect the reloading, a firing pin slidable in the breech bolt, a ring hammer and a primary sear cooperating with the hammer, the combination of the parts claimed in claim 12 together with a lever pivoted to the breech casing and located to contact with a depending edge of the cover, a spring position to urge the lever upwards, a disk fast with the lever and provided with a notch in its periphery, a projection on the tail of the primary sear located to enter the notch of the disk when the lever is depressed and to contact with the periphery of the disk when the lever is released by the cover, a lever pivoted in a depending edge of the cover near the lower margin thereof, a disk fast with the said lever, a pointed projection on the disk located to lie flush with the cover edge in one position and to project downwards in the other position, a seating on the breech casing below the disk, an L-shaped lever having horizontal and vertical arms and being pivoted at a point in its horizontal arm on the bolt and provided with a step in its vertical arm, spring means to urge the outer end of the horizontal arm downwards, the arrangement being that with the outer end of the horizontal arm depressed the step on the lever is in engagement with the head of the firing pin and the top end of the vertical arm is above the level of the part of the bolt behind the step.

ARNOLD LOUIS CHEVALLIER. THOMAS FREDERICK SANDERS. 

